Integration over curves and surfaces defined by the closest point mapping

We propose a new formulation for integrating over smooth curves and surfaces that are described by their closest point mappings. Our method is designed for curves and surfaces that are not defined by any explicit parameterization and is intended to be used in combination with level set techniques. However, contrary to the common practice with level set methods, the volume integrals derived from our formulation coincide exactly with the surface or line integrals that one wish to compute. We study various aspects of this formulation and provide a geometric interpretation of this formulation in terms of the singular values of the Jacobian matrix of the closest point mapping. Additionally, we extend the formulation - initially derived to integrate over manifolds of codimension one - to include integration along curves in three dimensions. Some numerical examples using very simple discretizations are presented to demonstrate the efficacy of the formulation.Comment: Revised the pape

Able-bodied wild chimpanzees imitate a motor procedure used by a disabled individual to overcome handicap

Fieldwork of CH was generously supported by grants from the Wenner-Gren Foundation (http://wennergren.org) and the Russell Trust. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Chimpanzee culture has generated intense recent interest, fueled by the technical complexity of chimpanzee tool-using traditions; yet it is seriously doubted whether chimpanzees are able to learn motor procedures by imitation under natural conditions. Here we take advantage of an unusual chimpanzee population as a 'natural experiment' to identify evidence for imitative learning of this kind in wild chimpanzees. The Sonso chimpanzee community has suffered from high levels of snare injury and now has several manually disabled members. Adult male Tinka, with near-total paralysis of both hands, compensates inability to scratch his back manually by employing a distinctive technique of holding a growing liana taut while making side-to-side body movements against it. We found that seven able-bodied young chimpanzees also used this 'liana-scratch' technique, although they had no need to. The distribution of the liana-scratch technique was statistically associated with individuals' range overlap with Tinka and the extent of time they spent in parties with him, confirming that the technique is acquired by social learning. The motivation for able-bodied chimpanzees copying his variant is unknown, but the fact that they do is evidence that the imitative learning of motor procedures from others is a natural trait of wild chimpanzees.Publisher PDFPeer reviewe

Productivity Spillovers to Domestic Plants from Foreign Direct Investment: Evidence from UK Manufacturing, 1974-1995

Empirical literature on the impact of FDI has considered at length the indirect spillover benefits that accrue to domestic plants as a result of FDI presence. However, the imprecise and disparate nature of spillovers makes accurate definition and indeed measurement of them difficult to achieve. In this paper, we consider the definition of what constitutes a spillover from FDI, and setout three main channels for spillovers; within (intra)industry, between (inter)industry and agglomeration. We then go on to measure the indirect impact of FDI on the total factor productivity of domestic plants in a number of UK manufacturing industries, 1974-1995, using a standard production function-based approach. We use data made available from the UK ARD and information derived from UK input-output tables, to establish the potential for inter-industry linkages. Our results indicate that the competition and ëabsorption capacityí effect at times outweighs any potential benefits, leading to negative spillovers. We also find that inter-industry spillovers are generally more prevalent than intra-industry spillovers. Generally, we do not find the agglomeration spillover to be significant. However, we conclude that the nature of spillovers is such that measurement techniques traditionally adopted fail to adequately explain their complex and diverse nature.

Genetic Monitoring in the Workplace: A Tool Not a Solution

The authors differentiate between genetic monitoring and screening, and discuss the potential risks and benefits of predictive testing technologies

BMP Signaling Goes Posttranscriptional in a microRNA Sort of Way

Aberrant microRNA (miRNA) expression correlates with human diseases such as cardiac disorders and cancer. Treatment of such disorders using miRNA-targeted therapeutics requires a thorough understanding of miRNA regulation in vivo. A recent paper in Nature by Davis et al. expands our understanding of miRNA biogenesis and maturation, elucidating a mechanism by which extracellular signaling directs cell differentiation via posttranscriptional regulation of miRNA expression

Liberalisation and divestiture in the UK energy sector

Over the past 10 years, the government has privatised two energy industries — gas and electricity — and is presently selling British Coal. Vickers and Yarrow (1988) point out that the privatisation of utilities has two components, for the sale of assets to the private sector may be accompanied by changes in industrial structure. It is possible to sell assets without liberalisation, just as it would be possible to liberalise a market without asset transfers.2 The three energy industries were privatised with very different structures and competitive environments. This paper examines the structures chosen in the light of the benefits to government, private producers and consumers, focusing on whether restructuring and liberalisation should occur before or after privatisation. A similar choice exists after flotation between divestiture and restructuring of the industry itself and changing the external competitive or regulatory environment. Within energy, we show that the structure chosen for one industry affects the options available for another, because of the complex interactions within the sector.

What makes a looked after child happy and unhappy?

What is good for a looked after child is usually decided by adults with the child’s voice often peripheral. One way to make the child central to decision-making is to ask them what makes them happy or unhappy. In doing this, the definition of happiness has to be neither a description of what has gone well in life nor an immediate state of mind, but should encompass the Aristotelian concept of eudaimonia. This is often translated as happiness but also incorporates notions of well-being and flourishing. The study reported here was undertaken as part of a children’s health needs assessment in an English local authority. It sought to understand why looked after children experience such high levels of poor mental health and make growing demands on therapeutic services. The proportion of young people displaying above average scores on validated measures, such as the Strengths and Difficulties Questionnaire (SDQ), is growing each year. The aim was to find out what looked after children say makes them happy and unhappy and what they see as likely to increase their well-being, and to compare their suggestions with those of the professionals and carers involved in their lives. Focus groups with children and professionals then discussed the same question, with the professionals also examining their understanding of SDQ results and their relevance to practice. The study found significant differences between the views of the children and professionals in both the range and emphasis of what is seen as important. Moreover, these adult assumptions were rarely tested by meaningful discussions with young people when key decisions were made; indeed, these seemed to be made about rather than with the children. In addition, the SDQ was not widely used by professionals to assess children’s emotional health and well-being needs. The study concluded that discussions about happiness can usefully support holistic understandings of looked after children’s experiences and aid planning and practice development

Self-Esteem, Spiritual Well-Being, and Intimacy: A Comparison among Couples Using NFP and Oral Contraceptives

The purpose of this study was to compare the intimacy, spiritual well being (SWB), and self-esteem of couples using natural family planning (NFP) with those couples using oral contraceptives (OCs). 22 couples who were using the Creighton Model Ovulation Method of NFP for 1 year to avoid pregnancy were matched with 22 couples who were using OCs for a least a 1-year period and administered a SWB, self-esteem, and intimacy inventory. Student t-tests were calculated to determine differences in the mean scores of the 3 inventories between the 2 groups. The results showed that the NFP couples had statistically higher self-esteem (T=3.15, p0.01), SWB (T=4.25. p0.001), and intellectual intimacy (T=2.53, p0.05) than the OC couples. There were no differences in emotional, social, recreational, and sexual intimacy between the groups. Although the results provide some evidence that NFP can enhance a couple\u27s relationship, other factors such as a sampling bias and educational levels could explain the difference

Opting Out Of The 48-Hour Week – Employer Necessity Or Individual Choice? An Empirical Study Of The Operation Of Article 18(1)(B) Of The Working Time Directive In The UK

The EU Working Time Directive has so far had little impact on an ingrained culture of long-hours working in the UK. Case studies suggest that the use of individual opt-outs from the 48-hour limit on weekly working time is a principal reason for this. However, removal of the individual opt-out (currently under consideration at EU level) is unlikely to make much difference to UK practice in the absence of a wider review of working time policy. In particular, the UK’s individualised system of workplace bargaining is currently ill-placed to adapt to a continental European model of working time regulation.working time, labour standards, collective bargaining, European Union